Vehicular emissions have become one of the main source of pollution of urban soils; this highlights the need for more detailed research on various traffic-related emissions and related distribution patterns. Since the banning of asbestos in the European Union, its substitution with antimony (Sb) in brake linings has led to increased inputs of this toxic metalloid to environmental compartments. The objective of this study was to provide detailed information about the spatial distribution patterns of Sb and to assess its mobility and bioavailability. Roadside soils along an arterial road (approx. 9000 vehicles per day) in Cologne (Germany) were studied along five transects, at four soil depths and at seven sampling points set at varying distances from the road (n = 140). For all samples, comprehensive soil characterization was performed and inverse aqua regia-extractable trace metal content was determined being pseudo-total contents. Furthermore, for one transect, also total Sb and a chemical sequential extraction procedure was applied (n = 28). Pseudo-total Sb for all transects decreased significantly with soil depth and distance from the road, reflecting a distribution pattern similar to that of other trace metals associated with brake lining emissions. Conversely, metals associated with exhaust emissions showed a convex distribution. The geochemical fractionation of Sb revealed the following trends: i) non-specifically sorbed Sb was <5%; ii) specifically sorbed Sb was only detected within 1 m distance from the road and decreased with depth; iii) Sb associated with poorly-crystalline Fe oxides decreased with distance from the road; and iv) content of Sb bounded to well-crystalline Fe oxides, and Sb present in the residual fraction remained relatively constant at each depth. Consequently, roadside soils appear to inhibit brake lining-related Sb contamination, with significant but rather low ecotoxicological potential for input into surface and groundwater.

车辆排放已成为城市土壤污染的主要来源之一。这凸显了需要对各种与交通相关的排放和相关的分配模式进行更详细的研究。自从欧洲联盟禁止使用石棉以来，在刹车片中用锑（Sb）替代了石棉，导致这种有毒准金属向环境舱室的输入增加了。这项研究的目的是提供有关Sb的空间分布模式的详细信息，并评估其迁移率和生物利用度。在科隆（德国）的一条动脉道路（每天约9000辆车）的路旁土壤沿五个断面，四个土壤深度和七个距道路不同距离的采样点（n = 140）进行了研究。对于所有样品，进行了全面的土壤表征，逆向王水提取的​​痕量金属含量被确定为伪总含量。此外，对于一个样带，还应用了总Sb和化学顺序萃取程序（n = 28）。随着土壤深度和距道路的距离，所有样点的伪总Sb显着降低，反映出与其他与刹车片排放有关的微量金属相似的分布方式。相反，与废气排放有关的金属呈凸形分布。Sb的地球化学分馏显示出以下趋势：i）非特异性吸附的Sb <5％。ii）仅在距道路1 m的距离内检测到特定吸附的Sb，并且随着深度的增加而降低；iii）与低结晶度的氧化铁有关的锑随距道路的距离而减少；iv）结合到结晶良好的Fe氧化物上的Sb含量，残留部分中存在的Sb在每个深度处都保持相对恒定。因此，路边土壤似乎抑制了刹车片相关的锑污染，具有显着但相当低的生态毒理潜力，可输入地表和地下水。